Abstract: Complex oxides are known to possess the full spectrum of fascinating properties, including magnetism, colossal magneto-resistance, superconductivity, ferroelectricity, piezoelectricity, multiferroicity, ionic conductivity, and more. This breadth of remarkable properties is the consequence of strong coupling among charge, spin, orbital, and lattice degrees of freedom. Spurred by recent advances in the synthesis of such artificial materials at the atomic scale, the physics of oxide heterostructures containing atomically smooth layers of such correlated electron materials with abrupt interfaces is a rapidly growing area. We have established a growth technique to control complex oxides at the level of unit cell thickness by pulsed laser deposition. The atomic-scale growth control enables to assemble materials from atoms to functional systems in a programmable manner, yielding many intriguing physical properties that cannot be found in bulk counterparts. In this talk, examples of functional materials will be presented, highlighting the importance of heterostructuring, interfacing, and straining. The main topics include (1) strain control of orbital polarization, oxygen mobility, and cationic distribution in perovskite oxides, (2) neutron probing of interfacial magnetism in a ferroelectric-ferromagnetic heterostructure and its control by ferroelectric and ionic-liquid gating.

*This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division.